Discussion of mapmaking works!

Could you at least share the plot of the final map?

Of course: it's as simple as pie. A great being observed the exploits of the heroes from previous campaigns and gathered them together in one kingdom-state: he promised new knowledge to some, immortality to others, money to some, and glory to others... And so, you need to reach the designated goal (along the way, of course, defeating enemies and gaining experience). And when you get there (there will be a surprise) - the climax (I won't reveal it yet).